Lightning strike protection of aircraft structural joints

Lightning protection of aircraft has been a topic considered by the aerospace industry for many years. Protection principles are well defined for traditional metallic aircraft; however, the move to using novel materials for structural components has produced new challenges for the aerospace industry. Surface damage to CFRP wing skin is commonly addressed by the introduction of a highly conductive surface layer. An additional concern is the potential for sparking within the fuel tank as a result of a lightning strike to a fastened CFRP joint. The paper describes the sparking joint problem and the corresponding certification requirements. It reviews current understanding of the sparking phenomenology and suggests the future direction for the development of lightning strike protection.